Adapted from the manga "Tomodachi Game" (トモダチゲーム) written by Yamaguchi Mikoto (山口ミコト) and illustrated and written by Sato Yuki (佐藤友生). Katagiri Yuichi is a second-year high school student who is abducted with four friends to repay a large amount of debt and he decides to participate in the mysterious "Tomodachi Game".